飞信发信息，解决证书问题

        private void button1_Click(object sender, EventArgs e)
        {
            ServicePointManager.ServerCertificateValidationCallback = ValidateServerCertificate;
            ServicePointManager.CertificatePolicy = new AcceptAllCertificatePolicy(); 
            string num = textBox1.Text;
            string contents = textBox2.Text;
            string url = "https://sms.api.bz/fetion.php?username=1511111111&password=11111111&sendto=" + num + "&message=" + contents;
            HttpWebRequest req = (HttpWebRequest)HttpWebRequest.Create(url);
            req.Method = "GET";
            using (WebResponse wr = req.GetResponse())
            {
                MessageBox.Show("OK");
            }

        }
        internal class AcceptAllCertificatePolicy : ICertificatePolicy
        {
            public AcceptAllCertificatePolicy()
            {
            }

            public bool CheckValidationResult(ServicePoint sPoint,
               X509Certificate cert, WebRequest wRequest, int certProb)
            {
                // Always accept 
                return true;
            }
        }
        private bool ValidateServerCertificate(object sender, X509Certificate certificate, X509Chain chain, SslPolicyErrors sslPolicyErrors)
        {
            return true;
        }